Abstract

The small carrion beetle Ptomaphagus hirtus is an abundant inhabitant of the exceptionally biodiverse Mammoth Cave system. Previous studies revealed negative phototaxis and the expression of biological clock genes in this microphthalmic cave beetle. Here we present results from probing P. hirtus for the entrainment of locomotor rhythms using the TriKinetics activity monitor setup. Although curtailed by low adjustment frequency of animals to the test environment, the data obtained from successfully monitoring two animals in constant darkness (DD) and six animals exposed to 12 hour light-dark cycles (LD) revealed a strong effect of light on locomotor activity in P. hirtus. In LD, activity was prevalent during the artificial night phases while close to absent during the presumptive day phases, suggesting conserved nocturnality. Upon transitioning LD animals to constant darkness, none displayed detectable evidence of free-running activity rhythms, suggesting complete regression of the central circadian clock. Equally notable, overall locomotor activity of the two DD-monitored animals was about three-fold lower compared to LD animals due to longer rest durations in the former. We, therefore, propose the existence of cave zone-specific energy expenditure modes that are mediated through light schedule responsive modification of sleep duration in P. hirtus.

Addeddate

2025-03-16 17:32:33

Bhl_virtual_titleid

211047

Bhl_virtual_volume

v.45 (2023)

Call number

10_3897_subtbiol_45_100717

Call-number

10_3897_subtbiol_45_100717

Foldoutcount

0

Genre

article

Identifier

evidenceancestr45royz

Identifier-ark

ark:/13960/s2z9zctwqp8

Identifier-bib

10_3897_subtbiol_45_100717

Identifier-doi

10.3897/subtbiol.45.100717

Ocr

tesseract 5.3.0-6-g76ae

Ocr_detected_lang

en

Ocr_detected_lang_conf

1.0000

Ocr_detected_script

Latin

Ocr_detected_script_conf

1.0000

Ocr_module_version

0.0.21

Ocr_parameters

-l eng

Page_number_confidence

80

Page_number_module_version

1.0.5

Page_range

75-94

Pages

20

Pdf_degraded

invalid-jp2-headers

Pdf_module_version

0.0.25

Possible copyright status

In copyright. Digitized with the permission of the rights holder.

Ppi

300

Source

Subterranean Biology 45

Year

2023

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